1. Field of the Invention
The present invention relates to controlling the output of picture signals and audio signals from equipment such as, for example, video tape recorders, laser disc players and digital audio tape machines in audio visual systems with suitable connection control equipment, initialization equipment and a suitable connection confirmation method.
2. Description of the Related Art
FIG. 33 is a block diagram showing an example structure of a prior art video system. The television 100 selects an object channel from the high frequency signal provided by the antenna by using the internally constructed tuner. This is then demodulated so that the picture signal and audio signal can be picked out and then output via, for example, a CRT and a speaker (both not shown in the diagram). The video cassette recorder (VCR) 30 and the laser disc player 50 which are connected in parallel with the television 100 via the external input terminals 25 and 26 are then selected to play pictures and audio as deemed necessary, with these pictures and audio then being supplied to the CRT and speaker. In addition to the external output terminals (not shown in the diagram) for the VCR 30 and laser disc player 50 both being connected in parallel with the external input terminals 25 and 26 for the television 100, their control terminals (not shown in the diagram) are also connected in series with the control signal terminal 24 for the television. Operations such as, for example, the turning on and off and the playing of pictures and audio from the VCR 30 and the laser disc player 50 can then be controlled by operating the operating panel for the VCR 30 and the laser disc 50 or by operating their exclusive remote controllers (not shown in the diagram).
As well as a remote controller for the television 100 there is also a remote controller for the VCR 30 and the laser disc player 50 giving a total of three remote controllers in all which have to be operated. As this makes the overall operation complicated, in the video system in FIG. 33 the control signal output from the remote controller 2 is supplied via the control signal terminal 24 so that both the VCR 30 and the laser disc player 50 can be controlled. Also, in the prior art, when making a connection with an object item of audio visual equipment in accordance with the D2B (audio/video bus protocol) standard, a trial and error connection process is used which runs through the various possible connection paths.
For example, in the conventional audio visual system shown in FIG. 34, when making a signal connection from the television 100 to the VCR 30, it is first confirmed if the path passing through the first audio/video switching controller is a possibility, and if it is, a connection instruction is output to the VCR 30 via the first audio/video switching controller 21.
However, if the first audio/video switching controller 21 is being used by the laser disc player 50, after it has been confirmed that a path through the first audio/video switching controller 21 is not possible, it is confirmed whether or not a path through the second audio/video switching controller 22 is possible. If it is possible, a connection instruction is output to the VCR 30 via the second audio/video switching controller 22 and a connection is executed by this path.
In the prior art example in FIG. 33, the VCR 30 and the laser disc player 50 are connected in parallel to the external input terminals 25 and 26 and are also connected in serial to the control signal terminal 24. After these connections have been carried out, an initialization process has to be carried out so that the television 100 can recognize the equipment connected at the external input terminals 25 and 26 (i.e. the VCR 30 and the laser disc player 50). It will then be possible to control (operate) the television 100, VCR 30 and the laser disc player 50 using the remote controller 2.
So, with the conventional television shown in FIG, 33, during initialization, if it cannot be confirmed that the VCR 30 and the laser disc player 50 are connected to the television 100 then it is likely that they are connected the wrong way around (as indicated by the dotted lines in the diagram). In order to then initialize the VCR 30 and the laser disc player 50 connected to the external input terminals 26 and 25, the user will first have to put the cables the right way around, which provides troublesome work for the user.
Herein, the present applicant put forward an application for a picture control apparatus where a picture for use in connection confirmation was put on one part of a CRT screen, with pictures being played from the apparatus connected to the external input terminals 25 and 26 then displayed so that confirmation of the connection conditions could be made (Japanese Patent Application No. Hei. 4-300391 [Picture Control Equipment, Electrical Appliance Control Equipment and Address Confirmation Method]).
However, this kind of picture control equipment was of no use, as a recording medium with a picture signal recorded on it had to be set up at the equipment connected to the external input terminals 25 and 26.
Also, in the connection control method used with the conventional audio/video system in FIG. 34, there was a problem whereby a long period of time elapses between the user operating the remote controller to output a signal connection instruction to the object audio visual equipment and the connection actually being set up.